Upgrade licenses are a good way of saving costs, especially in networks with a history. You have 20 Office 2007 Professional licenses and save cash, because you don’t purchase 20 full licenses for Office 2013, you purchase upgrade licenses. These licenses on their own are invalid. They need the proper base license (Office 2007) to cast them into full Office 2013 licenses. If you don’t have the base licenses, the upgrade licenses are useless.
The Lan-Inspector offers a solution to picture the connection of base licenses and upgrade licenses. To have a fully upgraded license, it is essential that the base license has no installation in the network. If you have an installation, your base license is consumed for it and it therefore cannot be used for the upgrade mode. The section about the license pool (see 6.5.1 License Pool / License Entry) talks about upgrade rules you can deposit into license entries. You get the information how upgrade relations/rules can be applied. If you have deposited these rules, they will be obeyed in your license balances.
On the other hand, it is possible to deposit downgrade rules. Downgrade rules can be applied if you got the case that your cannot purchase licenses anymore for an older software you are using in the network. There are several reasons why one would want to use the older software version rather than the new one. However, the downgrade rules can be edited in the downgrade editor, see 6.5.6 Downgrade Rules.
Please note that downgrades are nothing that can be applied as standards. Every software producer has his own rules and usually even every product has own rules for this. Some downgrade rights only apply if you have an additional Software Assurance (SA) from the producer. Please keep in mind that the Lan-Inspector is not a license consultant. If you are not sure how the license agreements need to be applied in your network, please ask a sophisticated license consultant.